Sjögren's syndrome is an autoimmune disorder in which immune cells attack and destroy the exocrine glands that produce tears and saliva. It is named after Swedish ophthalmologist Henrik Sjögren (1899-1986), who first described it. Sjögren's syndrome is also associated with rheumatic disorders such as rheumatoid arthritis, and it is rheumatoid factor positive in 90 percent of cases. The hallmark symptoms of this disorder are dry mouth and dry eyes (part of what are known as sicca symptoms). In addition, Sjögren's syndrome may cause skin, nose, and vaginal dryness, and may affect other organs of the body, including the kidneys, blood vessels, lungs, liver, pancreas, and brain. Nine out of ten Sjögren's patients are women and the average age of onset is late 40 s, although Sjögren's occurs in all age groups in both women and men. It is estimated to strike as many as 4 million people in the United States alone making it the second most common autoimmune rheumatic disease. Thus, there exists a clear need for better, more effective diagnostic and therapeutic methods for this condition. The present invention meets this and other related needs by identifying biomarkers, such as proteins and nucleic acids, present in human saliva that can be used for diagnosing Sjögren's syndrome.